This sounds very different from youth football here in the states. We play with 11 players on the field and have to follow all origninal alignment rules. Regardless of the differences, I would start the players on fundamental drills that you can find right on this website. I would focus alot of attention on ball exchanges (center to QB/QB to ballcarrier). I have found this to be a common problem coaching youth football. I would also limit formations and simplify the blocking scheme. Zone blocking can work but even that has to be adjusted according to some defenses. I think the teams that display good fundamentals on offense and diciplined defense have the greatest success. You don't have to razzle dazzle, it just confuses the kids.